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Abstract:

In a method of manufacturing a multilayer ceramic component, a ceramic
capacitor body is formed from electrode layers and dielectric layers.
First and second external terminals are attached on opposite ends of the
ceramic capacitor body. The ceramic capacitor body is coated to assist in
increasing breakdown voltage. The electrode layers include active
electrode layers configured in an alternating manner such that a first
end of the active electrodes extends from one end of the ceramic
capacitor body inwardly and a next internal active electrode extends from
an opposite end of the ceramic capacitor body inwardly. The active
electrode layer includes side shields to provide additional shielding.

Claims:

1. A method of manufacturing a multilayer ceramic component, comprising:
forming a ceramic capacitor body from a plurality of electrode layers and
dielectric layers; attaching first and second external terminals on
opposite ends of the ceramic capacitor body; and coating the ceramic
capacitor body to assist in increasing breakdown voltage; wherein the
plurality of electrode layers comprises layers of active electrodes and
layers of shielding electrodes and wherein the layers of active
electrodes are configured in an alternating manner such that a first of
the plurality of active electrodes extends from one end of the ceramic
capacitor body inwardly and a next internal active electrode extends from
an opposite end of the ceramic capacitor body inwardly; wherein the
layers of shielding electrodes comprise a top internal electrode shield
and an opposite bottom internal electrode shield wherein the top internal
electrode shield and the opposite bottom internal electrode shield are on
opposite sides of the plurality of active electrodes and each electrode
shield extends inwardly to or beyond a corresponding external terminal to
provide shielding; wherein the layers of active electrodes further
comprise layers of side shields on opposite sides of the active
electrodes to provide additional shielding.

2. The method of claim 1 wherein the coating comprises depositing a
polyimide on an outer surface of the ceramic capacitor body.

3. The method of claim 1 wherein the coating is spin coated.

4. A method of manufacturing a multilayer ceramic component, comprising:
forming a ceramic capacitor body from a plurality of electrode layers and
dielectric layers; attaching first and second external terminals on
opposite ends of the ceramic capacitor body; and coating the ceramic
capacitor body; wherein the plurality of electrode layers comprises
layers of active electrodes and layers of shielding electrodes and
wherein the layers of active electrodes are configured in an alternating
manner such that a first of the plurality of active electrodes extends
from one end of the ceramic capacitor body inwardly and a next internal
active electrode extends from an opposite end of the ceramic capacitor
body inwardly; wherein the layers of active electrodes further comprise
layers of side shields on opposite sides of the active electrodes to
provide shielding.

5. The method of claim 4 wherein the coating comprises depositing a
polyimide on an outer surface of the ceramic capacitor body.

6. The method of claim 4 wherein the coating is spin coated.

7. A method of manufacturing a multilayer ceramic component, comprising:
forming a ceramic capacitor body from a plurality of electrode layers and
dielectric layers; attaching first and second external terminals on
opposite ends of the ceramic capacitor body; and coating the ceramic
capacitor body to assist in increasing breakdown voltage; wherein the
plurality of electrode layers comprises layers of active electrodes and
layers of shielding electrodes and wherein the layers of active
electrodes are configured in an alternating manner such that a first of
the plurality of active electrodes extends from one end of the ceramic
capacitor body inwardly and a next internal active electrode extends from
an opposite end of the ceramic capacitor body inwardly; wherein the
layers of shielding electrodes comprise a top internal electrode shield
and an opposite bottom internal electrode shield wherein the top internal
electrode shield and the opposite bottom internal electrode shield are on
opposite sides of the plurality of active electrodes and each electrode
shield extends inwardly to or beyond a corresponding external terminal to
provide shielding; wherein the layers of active electrodes further
comprise side shields to provide additional shielding.

8. A method of manufacturing a multilayer ceramic component, comprising:
forming a ceramic capacitor body from a plurality of electrode layers and
dielectric layers; attaching first and second external terminals on
opposite ends of the ceramic capacitor body; and coating the ceramic
capacitor body to assist in increasing breakdown voltage; wherein the
plurality of electrode layers comprises active electrodes and shielding
electrodes and wherein the active electrodes are configured in an
alternating manner such that a first of the plurality of active
electrodes extends from one end of the ceramic capacitor body inwardly
and a next active electrode extends from an opposite end of the ceramic
capacitor body inwardly; wherein the layers of active electrodes further
comprise side shields to provide shielding.

9. A method of manufacturing a multilayer ceramic component, comprising:
forming a ceramic capacitor body from a plurality of electrode layers and
dielectric layers; attaching first and second external terminals on
opposite ends of the ceramic capacitor body; and coating the ceramic
capacitor body to assist in increasing breakdown voltage; wherein the
plurality of electrode layers comprises a plurality of active electrode
layers being configured in an alternating manner such that a first end of
the plurality of active electrodes extends from one end of the ceramic
capacitor body inwardly and a next internal active electrode extends from
an opposite end of the ceramic capacitor body inwardly; wherein the
active electrode layer further comprises side shields to provide
additional shielding.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of U.S. patent application Ser.
No. 12/189,492, filed Aug. 11, 2008, now U.S. Pat. No. 8,238,075, and a
continuation-in part of PCT Application No. PCT/US06/23338, filed Jun.
15, 2006, which claims priority to U.S. patent application Ser. No.
11/359,711 filed Feb. 22, 2006, now U.S. Pat. No. 7,336,475, which are
incorporated by reference as if fully set forth.

BACKGROUND

[0002] Multilayer ceramic capacitors generally have alternating layers of
ceramic dielectric material and conductive electrodes. Various types of
dielectric materials can be used and various types of physical
configurations have been used. Capacitors for high voltage performance
have been produced for many years using a "series design". In the series
design the charge is stored between the floating electrode and electrodes
connected to the terminals on either side as shown for a single floating
electrode designs in FIG. 1. This compares to a standard capacitor design
shown in FIG. 2 in which the electrodes alternatively connect to
different terminals and the charge is stored between these electrodes.
The capacitance for these designs is given by:

[0008] However, in the case of the series design the effective overlap
area is significantly reduced. The advantage of the series design is that
the internal voltage acting on the electrodes is halved for the single
floating electrode. It is possible to further separate the floating
electrode to give more than one floating electrode per layer to reduce
the internal voltage but this also lowers the effective overlap area
reducing capacitance. The average voltage breakdowns (n=50) for 27 lots
of case size 1812 MLCCs, 47 nF±10% standard designs and the same
number of case size 1812, 22 nF±10% single floating electrode series
designs are shown in FIG. 3. In all these cases the fired active
thickness separating the electrodes was 0.0023'', 58 microns with an
overall thickness of 0.051±0.003'' (1.30±10 0.08 mm) for the
standard design and 0.068±0.003'' (1.73±0.08 mm) for the series
capacitors. The length and width dimensions were 0.177±0.0 10''
(4.50±0.25 mm) and 0.126±0.008'' (3.20±0.20 mm) respectively for
all these 18 12 case size capacitors. Cross-sections of the 1812 standard
design and the single electrode series design are shown in FIGS. 4 and 5
respectively.

[0009] In addition to the internal voltage withstanding capability of
these MLCCs it is also critical that these parts are resistant to
arc-over from the capacitor terminals. U.S. Pat. No. 4,731,697, to
McLarney discloses a surface electrode with portions of the margin
covered by a further dielectric layer to prevent arc over that requires
laser trimming. However, it is important to note that exposed electrodes
are subject to corrosion. Also the properties of exposed electrodes are
significantly impacted by the environment factors, such as humidity,
limiting the applications in which these capacitors can be used.

[0010] U.S. Pat. No. 6,627,509 to Duva discloses a method for producing
surface flashover resistant capacitors by applying a para-poly-xylylene
coating to the surface of multilayer ceramic capacitors followed by
trimming the excess material from the terminals. In this case significant
costs are associated with coating of the capacitors. Furthermore, the
coating may not be compatible with the circuit board assembly processes
and the presence of organic coatings in some electronic application such
as satellites is limited because of out gassing concerns.

[0011] Thus, despite various efforts to reduce produce capacitors with
high voltage breakdown and which minimize occurrence of arc over,
problems remain. What is needed is an improved high voltage capacitor.

SUMMARY

[0012] Therefore, it is a primary object, feature, or advantage of the
present invention to improve upon the state of the art.

[0013] It is a further object, feature, or advantage of the present
invention to provide a multilayer ceramic capacitor which is resistant to
arc-over.

[0014] It is a still further object, feature, or advantage of the present
invention to provide a multilayer ceramic capacitor with high voltage
breakdown in air.

[0015] A still further object, feature, or advantage of the present
invention is to provide a multilayer ceramic capacitor with a design
which retains high capacitance.

[0016] Another object, feature, or advantage of the present invention is
to minimize the occurrence of unwanted disruptions due to arc-over when
the capacitor is incorporated into an electronic circuit.

[0017] Yet another object, feature, or advantage of the present invention
is to provide a capacitor with high voltage withstanding capability with
a smaller case size allowing for miniaturization of circuits.

[0018] A further object, feature, or advantage of the present invention is
to provide an improved capacitor which can be manufactured conveniently
and economically.

[0019] One or more of these and/or other objects, features, or advantages
of the present invention will become apparent from the specification and
claims that follow.

[0020] According to one aspect of the present invention, a multilayer
ceramic capacitor component is provided. The capacitor component includes
a ceramic capacitor body having opposite ends and comprised of a
plurality of electrode layers and dielectric layers. The capacitor
component further includes first and second external terminals attached
to the ceramic capacitor body. The capacitor component also includes a
plurality of internal active electrodes within the ceramic capacitor body
configured in an alternating manner such that a first of the plurality of
internal active electrodes extends from one end of the ceramic capacitor
body inwardly and a next internal active electrode extends from an
opposite end of the ceramic capacitor body inwardly. There is also a
plurality of internal electrode shields within the ceramic capacitor body
to thereby assist in providing resistance to arc-over. The plurality of
internal electrode shields include a top internal electrode shield and an
opposite bottom internal electrode shield wherein the top internal
electrode shield and the opposite bottom internal electrode shield are on
opposite sides of the plurality of internal active electrodes and each
internal electrode shield extends inwardly to or beyond a corresponding
external terminal to thereby provide shielding. There are also side
shields. Each side shield extends inwardly from one end of the capacitor
body and the side shields are configured to further shield an active
electrode to thereby further resist arc over between active electrodes
and terminals. A coating is on the ceramic capacitor body to assist in
increasing breakdown voltage.

[0021] According to another aspect of the present invention, a multilayer
ceramic capacitor component for providing improved high voltage
characteristics is provided. The capacitor includes a ceramic capacitor
body having opposite ends and comprised of a plurality of electrode
layers and dielectric layers. First and second external terminals are
attached to the ceramic capacitor body. The plurality of electrode layers
include a top layer having an electrode shield extending inwardly to or
beyond the first terminal, a bottom layer having an electrode shield
extending inwardly to or beyond the second terminal, and a plurality of
alternating layers of active electrodes extending inwardly from
alternating ends of the ceramic capacitor body. Each of the alternating
layers of active electrodes also includes side shields. A coating on the
ceramic capacitor body assists in increasing breakdown voltage.

[0022] According to another aspect of the present invention a method of
manufacturing a multilayer ceramic component is provided. The method
includes forming a ceramic capacitor body from a plurality of electrode
layers and dielectric layers and attaching first and second external
terminals on opposite ends of the ceramic capacitor body. The plurality
of electrode layers comprises layers of active electrodes and layers of
shielding electrodes and wherein the layers of active electrodes are
configured in an alternating manner such that a first of the plurality of
active electrodes extends from one end of the ceramic capacitor body
inwardly and a next internal active electrode extends from an opposite
end of the ceramic capacitor body inwardly. The layers of shielding
electrodes include a top internal electrode shield and an opposite bottom
internal electrode shield wherein the top internal electrode shield and
the opposite bottom internal electrode shield are on opposite sides of
the plurality of active electrodes and each electrode shield extends
inwardly to or beyond a corresponding external terminal to thereby
provide shielding. The layers of active electrodes also include layers of
side shields on opposite sides of the active electrodes to thereby
provide additional shielding. A coating on the ceramic capacitor body
assists in increasing breakdown voltage.

[0023] A multilayer ceramic capacitor component comprising a ceramic
capacitor body having opposite ends and comprised of a plurality of
electrode layers and dielectric layers; first and second external
terminals attached to the ceramic capacitor body; a plurality of internal
active electrodes within the ceramic capacitor body configured in an
alternating manner such that a first of the plurality of internal active
electrodes extends from one end of the ceramic capacitor body inwardly
and a next internal active electrode extends from an opposite end of the
ceramic capacitor body inwardly; a plurality of internal electrode
shields within the ceramic capacitor body to thereby assist in providing
resistance to arc-over; the plurality of internal electrode shields
comprising a plurality of side shields, each side shield extending
inwardly from one end of the capacitor body and the side shields
configured to shield a corresponding active electrode to thereby resist
arc over between active electrodes and terminals; and a coating on the
ceramic capacitor body to assist in increasing breakdown voltage.

[0024] A method of manufacturing a multilayer ceramic component,
comprising forming a ceramic capacitor body from a plurality of electrode
layers and dielectric layers; attaching first and second external
terminals on opposite ends of the ceramic capacitor body; coating the
ceramic capacitor body; wherein the plurality of electrode layers
comprises layers of active electrodes and layers of shielding electrodes
and wherein the layers of active electrodes being configured in an
alternating manner such that a first of the plurality of active
electrodes extends from one end of the ceramic capacitor body inwardly
and a next internal active electrode extends from an opposite end of the
ceramic capacitor body inwardly; wherein the layers of active electrodes
further comprise layers of side shields on opposite sides of the active
electrodes to thereby provide shielding.

[0025] A multilayer ceramic capacitor component comprising a ceramic
capacitor body having opposite ends and comprised of a plurality of
electrode layers and dielectric layers; first and second external
terminals attached to the ceramic capacitor body; a plurality of internal
active electrodes within the ceramic capacitor body configured in an
alternating manner such that a first of the plurality of internal active
electrodes extends from one end of the ceramic capacitor body inwardly
and a next internal active electrode extends from an opposite end of the
ceramic capacitor body inwardly; a plurality of internal electrode
shields within the ceramic capacitor body to thereby assist in providing
resistance to arc over; each of the internal electrode shield extends
inwardly to or beyond a corresponding external terminal to thereby
provide shielding; the plurality of internal electrode shields comprising
a plurality of side shields, each side shield extending inwardly from one
end of the capacitor body and the side shields configured to shield the
internal active electrode to thereby further resist arc over between the
internal active electrodes and the terminals; and a coating on the
ceramic capacitor body to assist in increasing breakdown voltage.

[0026] A multilayer ceramic capacitor component for providing improved
high voltage characteristics, comprising a ceramic capacitor body having
opposite ends and comprised of a plurality of electrode layers and
dielectric layers; first and second external terminals attached to the
ceramic capacitor body; wherein the plurality of electrode layers
comprise a top layer having an electrode shield extending inwardly to or
beyond the first terminal, a bottom layer having an electrode shield
extending inwardly to or beyond the second terminal, and a plurality of
alternating layers of active electrodes extending inwardly from
alternating ends of the ceramic capacitor body; a plurality of side
shields disposed within the plurality of alternating layers of active
electrodes to provide shielding; and a coating on the ceramic capacitor
body to assist in increasing breakdown voltage.

[0027] A method of manufacturing a multilayer ceramic component,
comprising forming a ceramic capacitor body from a plurality of electrode
layers and dielectric layers; attaching first and second external
terminals on opposite ends of the ceramic capacitor body; coating the
ceramic capacitor body to assist in increasing breakdown voltage; wherein
the plurality of electrode layers comprises layers of active electrodes
and layers of shielding electrodes and wherein the layers of active
electrodes being configured in an alternating manner such that a first of
the plurality of active electrodes extends from one end of the ceramic
capacitor body inwardly and a next internal active electrode extends from
an opposite end of the ceramic capacitor body inwardly; wherein the
layers of shielding electrodes comprise a top internal electrode shield
and an opposite bottom internal electrode shield wherein the top internal
electrode shield and the opposite bottom internal electrode shield are on
opposite sides of the plurality of active electrodes and each electrode
shield extends inwardly to or beyond a corresponding external terminal to
thereby provide shielding; wherein the layers of active electrodes
further comprise side shields to thereby provide additional shielding.

[0028] A multilayer ceramic capacitor component comprising a ceramic
capacitor body having opposite ends and comprised of a plurality of
electrode layers and dielectric layers; first and second external
terminals attached to the ceramic capacitor body; a plurality of internal
active electrodes within the ceramic capacitor body configured in an
alternating manner such that a first of the plurality of internal active
electrodes extends from one end of the ceramic capacitor body inwardly
and a next internal active electrode extends from an opposite end of the
ceramic capacitor body inwardly; a plurality of internal electrode
shields within the ceramic capacitor body to thereby assist in providing
resistance to arc over; the plurality of internal electrode shields
comprising a plurality of side shields, each side shield extending
inwardly from one end of the capacitor body to thereby resist arc over
between active electrodes and terminals; and a coating on the ceramic
capacitor body to assist in increasing breakdown voltage.

[0029] A method of manufacturing a multilayer ceramic component,
comprising forming a ceramic capacitor body from a plurality of electrode
layers and dielectric layers; attaching first and second external
terminals on opposite ends of the ceramic capacitor body; coating the
ceramic capacitor body to assist in increasing breakdown voltage; wherein
the plurality of electrode layers comprises active electrodes and
shielding electrodes and wherein the active electrodes being configured
in an alternating manner such that a first of the plurality of active
electrodes extends from one end of the ceramic capacitor body inwardly
and a next active electrode extends from an opposite end of the ceramic
capacitor body inwardly; wherein the layers of active electrodes further
comprise side shields to thereby provide shielding.

[0030] A method of manufacturing a multilayer ceramic component,
comprising forming a ceramic capacitor body from a plurality of electrode
layers and dielectric layers; attaching first and second external
terminals on opposite ends of the ceramic capacitor body; coating the
ceramic capacitor body to assist in increasing breakdown voltage; wherein
the plurality of electrode layers comprises a plurality of active
electrode layers being configured in an alternating manner such that a
first end of the plurality of active electrodes extends from one end of
the ceramic capacitor body inwardly and a next internal active electrode
extends from an opposite end of the ceramic capacitor body inwardly;
wherein the active electrode layer further comprise side shields to
thereby provide additional shielding.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 is a diagram of a cross-section through a series capacitor
design with a single floating electrode.

[0032] FIG. 2 is a diagram of a cross-section through a standard capacitor
sign.

[0033]FIG. 3 shows an average voltage breakdown of series and standard
capacitor 10 designs.

[0052]FIG. 14B is a photograph of an end view of the cross-section of
Example 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0053] This invention describes a novel arrangement of internal electrodes
that results in an arc resistant multilayer ceramic capacitor with very
high voltage breakdown in air. Furthermore these designs retain a high
capacitance. To assist in describing the present invention, each of three
designs and MLCC performance is described and then a more detailed
description of each example is provided with reference to the drawings.
The designs and MLCC performance is described in the following examples.

EXAMPLE 1

[0054] A standard case size 1206 capacitor design was manufactured using a
production MLCC X7R materials system C-153.

EXAMPLE 2

[0055] A case size 1206 capacitor design was manufactured using a
production MLCC X7R materials system C-153 with shield electrodes on top
and bottom. The purpose of these shield electrodes is to prevent an
arc-over between the terminal and the internal electrode of opposite
polarity or across the top or bottom surface of the capacitor between
terminals of opposite polarity. For this reason it is only necessary to
have one shield electrode present in the case where the active below is
of opposite polarity. However, during the course of manufacturing
capacitors of different values by shielding both terminal areas at the
top and bottom of the capacitor there is no need to change the screens
for different numbers of electrodes improving manufacturability.

EXAMPLE 3

[0056] A case size 1206 capacitor design was manufactured using a
production MLCC X7R materials system C-153 with side shield electrodes on
either side of the active in additions to shield electrodes on top and
bottom. The purpose of the side shield electrode is to prevent an
arc-over between the terminal and different internal electrode layers of
opposite polarity or across the sides of the capacitor between terminals
of opposite polarity. As for the top and bottom side shield electrodes,
two side shield electrodes on each side were used but it is only
necessary to have one side shield electrode at the side of each layer
with terminal of opposing polarity. The two side shield electrodes on
each side allow to accurately check alignment of the electrode stack.

[0057] The design and electrode pattern for all three examples is shown in
FIG. 6. Terminals were applied to these examples consisting of a thick
film fired silver paste and these were then over plated with nickel
followed by tin. The pasts were screened through a 1000V Hi-Pot and IR
verified. The average capacitances (n=100) and dimensions (n=5) were
measured as shown in FIG. 7.

[0058] It can be seen that the Number of Electrodes-1 (N) are almost the
same for all these examples, 27±1. The Fired Active Thickness of
Ceramic Separating the Layers (T) is also the same for all three examples
and since the same ceramic material system was used to manufacture all
the capacitors the Permittivity (Er) is the same. The only variable
affecting capacitance is therefore the Effective Overlap Area of
Electrodes (A). This is lower for Example 3 because of the presence of
the side-shields. The actual cross-sections of Examples 1, 2 and 3 are
shown in FIGS. 12A and 12B (Example 1), FIGS. 13A and 13B (Example 2) and
FIGS. 14A and 14B (Example 3).

[0059] A sample of 50 capacitors for examples 1, 2 and 3 were tested to
failure by applying voltage at a ramp rate of 500 V/s per method 103 of
EIA 198-2-E. The results are shown in FIG. 11. The instrument used for
testing was the Associated Research 75 12 DT HiPot. Data of FIG. 11
represents dielectric breakdown voltage levels, which include arc-over
and or physical destruction. Post IR testing of Example 1 parts had 13/50
Insulation Resistance (IR) failures, Examples 2 and 3 had 48/50 and 50/50
IR failures respectively indicating that failures due to arc-over were
not observed in Example 3. It is also important to note that repeated
arc-over occurrences on applying voltage would eventually cause IR
failure.

[0060] It can clearly be seen that Example 3 has the highest average
voltage breakdown >2.5 kV of the examples cited. The voltage breakdown
and capacitance of the 1206 case size capacitor in Example 3 are similar
to the 1812 1000V rated single floating electrode serial capacitors
described in the prior art. The capacitors described in Example 3
therefore allow the circuits required to handle high voltages to be
significantly miniaturized.

[0061] FIG. 1 illustrates a prior art capacitor design. In FIG. 1, a
capacitor 10 is shown with a first terminal 12 and an opposite second
terminal 14 on the opposite end of the capacitor body 16. Floating
electrodes 18 are shown. FIG. 2 illustrates another prior art capacitor
design. In FIG. 2, instead of floating electrodes, the electrodes
alternate. FIG. 3 compares the series and standard designs. In
particular, FIG. 3 shows the average voltage breakdowns (n=50) for 27
lots of case size 1812 MLCCs, 47 nF±10 percent standard designs and
the same number of case size 1812, 22 nF±10 percent single floating
electrode series designs. In all these cases the fired active thickness
separating the electrodes was 0.0023'', 58 microns with an overall
thickness of 0.051±0.003'' (1.30±0.08 mm) for the standard design
and 0.068±0.003'' (1.73±0.08 mm) for the series capacitors. The
length and width dimensions were 0.177±0.010'' (4.50±0.25 mm) and
0.126±0.008'' (3.20 ±0.20 mm) respectively for all these 1812 case
size capacitors. Cross-sections of the 1812 standard design and the
single electrode series design are shown in FIGS. 4A-4B and 5A-10 5B,
respectively.

[0062]FIG. 6 is a table which shows three different capacitor design
examples. The first example is a standard design used for comparison
purposes. The second example is one embodiment of the present invention
where top and bottom shields are used. The third example is another
embodiment of the present invention where both top and bottom shields as
well as side shields are used.

[0063] As shown in FIG. 6, in the standard design, the fired active
thickness of the capacitor is 0.0020 inches or 51 microns. The standard
design includes 26 active electrodes. In the top/bottom shield design,
the fired active thickness of the capacitor is also 0.0020 inches or 51
microns. The top/bottom shield design includes 27 active 20 electrodes.
In the top/bottom and side shield design, the fired active thickness is
0.0020 inches or 51 microns. In the top/bottom side shield design there
are 28 active electrodes.

[0064]FIG. 6 also shows the electrode layout plans for the various types
of design. According to the standard design there is a first electrode 20
and a staggered second electrode 22. A third electrode 24 is aligned with
the first electrode 20. A fourth electrode 26 is aligned with the second
electrode 22. This alternating pattern continues, with additional
alternating electrodes until the second to last electrode, N-1, and the
last electrode 30.

[0065] In the top/bottom shield design the first electrode layer includes
a first top shield 32 and a second top shield 34 as well as a first
bottom shield 36 and a second bottom shield 38. It is of particular note
that only the first top shield 32 and the second bottom shield 38 are
active-the other shields need not even be present. The first top shield
32 and second bottom shield 38 are necessary to prevent arc-over from
terminations of opposed polarity and shields 34 and 26 are present for
manufacturing convenience.

[0066] In the top/bottom and side shields embodiment, there is a first top
shield 32 and a second top shield 34 as well as a first bottom shield 36
and a second bottom shield 38. For each active electrode there are also
side shields 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68,
and 70. The side shields 40, 42, 52, 54, 56, 58, 68, and 70 are required
to protect the inner active electrodes from arc over from the termination
of opposed polarity whereas the other side shields were included to test
the electrode alignment within the parts.

[0067] The designs shown in FIG. 6 are further illustrated in FIGS. 8A to
10B. FIG. 8A is a cross-section of Example 1 (standard design) while FIG.
8B is an end view of the cross-section of Example 1. In FIG. 8A, a
multilayer ceramic capacitor component 48 is shown with a first terminal
12 and a second terminal 14 on opposite ends of a multilayer ceramic
capacitor component 16. The internal active electrodes of the ceramic
capacitor body are configured in alternating manners such that a first
internal active electrode 20 extends from one end of the ceramic
capacitor body inwardly toward the terminal on the opposite end of the
ceramic capacitor body. The next internal active electrode 22 extends
from the opposite end of the ceramic capacitor body inwardly toward the
terminal on the opposite end of the ceramic body. A coating 17 may be
used to further assist in increasing breakdown voltage. The end view
cross-section of FIG. 8B illustrates the electrodes.

[0068] FIG. 9A is a side view cross-section of Example 2 (top/bottom
shields) while FIG. 9B is an end view of the cross-section of Example 2.
In FIG. 9A, a multilayer ceramic capacitor component 50 is shown. Note
the presence of the internal electrode shields within the ceramic
capacitor body which assist in providing resistance to arc-over between
the terminals and internal electrodes. The internal electrode shields
shown include a top internal electrode shield 32 and an opposite bottom
internal electrode shield 38. The top internal electrode shield 32 and
the opposite bottom internal electrode shield 38 are on opposite sides of
the multilayer ceramic capacitor body 16. Each internal electrode shield
32, 38 extends inwardly to or beyond a corresponding terminal 12, 14 to
thereby provide shielding. As previously mentioned, additional structures
34, and 36 are provided but are not required as they do not provide
actual shielding due to the polarity of the terminals. They are included
for convenience in the manufacturing process. In addition, a coating 17
may be used to further assist in increasing breakdown voltage.

[0069] FIG. 10A is a side view cross-section of Example 3 (top/bottom
shields and side shield) while FIG. 10B is an end view of the
cross-section of Example 3. The multilayer ceramic capacitor 60 of FIG.
10A includes not only the top shield 32 and opposite bottom shield 38,
but also side shields. The side shields are best shown in FIG. 10B that
depicts a cross-section through the capacitor. The side shield in
question depends on the depth of the cross-section hence the side shields
shown are 40, 42, 48, and 50.

[0070]FIG. 7 provides a table for comparing the standard design to two
designs according 10 to the present invention. The table shows the
average capacitance and dimensions for the capacitor designs of FIG. 6.

[0071] FIG. 11 shows a voltage breakdown of Examples 1, 2 and 3. Note that
in FIG. 11, the top/bottom shield embodiment (Example 2) provides
increased voltage break down relative to the standard design (Example 1).
The top/bottom and side shield embodiment (Example 3) provides further
increased break down voltage. Thus, the present invention can be used to
create multi-layer ceramic capacitors having voltage breakdowns above
1000V, 1500V, 2000V, 2500V, or even 3000V.

[0072] The present invention further contemplates that a coating may be
used to further improve voltage breakdown performance. In particular, a
coating such as a polyimide coating may be used for improved voltage
breakdown performance. The coating may be spin coated. Testing may be
performed by subjecting the capacitor to voltage breakdown testing in air
after applying and curing a polyimide coating on the ceramic surface. The
use of the coating assists in increasing breakdown voltage. As standard
multilayer ceramic capacitor component of 100 nf capacitance and 1812
package size was subjected to voltage breakdown testing in air both with
and without coating with polyimide using spin coating techniques. The
uncoated capacitors had an average voltage breakdown of 1.27 RVDC while
the coated capacitors had an average breakdown voltage of 2.46 RVDC.
Thus, the use of the polyimide resulted in a significant improvement in
breakdown voltage.

[0073] Therefore an improved high voltage capacitor has been disclosed.
The present invention is not to be limited to the specific embodiments
shown in here. For example, the present invention contemplates numerous
variations in the types of dielectric used, types of conductors used,
sizes, dimensions, packaging, and other variations.